GTM-R Prototype - Hooked on Driving

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GTM-R Prototype
Race Car Built with Support
From Home Depot:
Not as a Sponsor – as a Parts Supplier!
By: David Ray, www.hookedondriving.com
For: The Wheel
GTM-R
Jeff Trout, a former student of mine from SCCA competition licensing school called me a couple
of months ago. He said he’s involved in a prototype race car that comes from a Factory Five
GTM kit package and has been built up into a serious road racing competitor. “Oh, cool,” I said.
Having written a story last month on a top-of-the-line supercharged Jag, I was, to tell the truth,
not all that excited to hear about a kit, home-built race car. But I remembered Jeff as a very
strong driver in licensing school, and while I’d lost track of him while he was racing in NASA, I
figured what he was involved with was a credible effort. So we made a deal to bring the car up
to a Hooked On Driving event and give it a go at Thunderhill.
GTM
First, Richard Migliori, the team owner behind this effort was shrewd in having me try out his
wife Yvonne’s street version of the GTM. Set up for a 5’6” lady driver, I took a few laps in this
svelte and gorgeous sports car with my head askew….not even close to fitting in the car. This
experience was quite frankly what I expected. The build of the car was nicely done, the design
and execution of the car itself was very impressive, but the drive was on the scary side. With
some teething issues remaining with the clutch, street tires and brakes, and a stiff, no-forgiveness
suspension that encouraged one to swap ends of the car with anything but perfect and smooth
steering input – this GTM street car was a thing of beauty, but not for the track without further
refinement. So there we go, suspicions confirmed, the kit car feel with the anticipated lack of
development was there for any driver to behold – the race car must be a REAL handful. This is
where the introduction to the article ends and the description of my religious experience begins.
OK – let’s get it over with – I suit up and climb in the GTM-R. Hum….the car looks similar but
that’s all – things are very different. With a single seat amidships, I’m able to snake into the car
and settle in – wow – very, very nice fit for a taller driver and a wonderful sense of security with
lots of side impact area, a panoramic view over the low-profile windshield, and the seat fits just
right. At least I’m not going to get a neck ache while I drive this mystery car. Pedals laid out
well, I notice the Home Depot shrink wrap on some of the interior bulkhead trim – yes, the car
has a number of “components” acquired from the Stockton Home Depot. I mention this and I
realize that this is what the car is all about. Richard is very proud to talk about the economy used
in building this supercar – but is it a supercar? I guess we’re going to find out….
Onto the track I go in the GTM-R. We’re joining the “D” group of very quick race prepped cars
with ideal conditions. My experience with HOD comes in to play in this situation. I have the
good fortune of having driven a LOT of different cars at Thunderhill, so it doesn’t take long for
me to get a feel for one on the track. By the time I get through Turn 2 the first lap, the car has
caught my interest. Wow – that was very smooth and the car feels quite well-balanced. Turn-in
was race-car crisp and there is NONE of the street car twitches. Maybe this won’t be so bad
after all. I squeeze on the throttle, then touch the brakes to settle her into off-camber Turn 3 and
the car floats nicely over the rise and like an old friend I fall into my favorite line with the car
pretty near the edge as the rear end feels close to sliding but behaves itself quite nicely. As I get
some good momentum through the right/left Turn 4 sequence, we’ve got some good momentum
up the hill headed to the Cyclone turn 5. Ah…the brakes feel soft – pedal not firm – mild
concern for a micro-second, but with additional pressure they respond. But we’re not really
going yet, or are we? It seems that the car felt comfortable enough to just start driving it….by
Turn 8, my confidence was building and I started reaching for full throttle. Power is nice – not
scary – this is a “tired” LS-6 motor with around 400HP, but in a 2400 lb package, it gets with the
program very well. Right now, you’re wondering a bit more of the specs on the car – well I’ll
tell you those when I’m done talking about the drive….that’s only fair as I didn’t know them til I
got out of the car – I was just driving for driving’s sake at this point. Coming around Turn 15
onto the straight I see the GTM-R team on the fence and my ego kicks in….maybe this car is fast
and I can show off a bit….we fly down the straight, almost redline 5th gear, and the religious
experience is well underway. The car is a joy to drive – the aero is definitely a factor over 80
mph – the car sticks great in Turn 2 – this time at a faster pace. This is my personal version of a
skid pad and I leave knowing there was a lot left. Looking back at my laps in the car, I know I
didn’t get even close to the limits….As the session moves on we get a few sprinkles of rain.
Enough to dampen the track a bit and send most cars into the paddock. But I knew this was my
only chance to drive the car so I stayed out on the Hoosier RA6’s and was rewarded. The timing
was perfect for me to put in a couple of tiptoe laps focusing on smoothing out and just getting
more comfortable with the gearbox, footwork etc…and I was rewarded. In just a few minutes
the wet sheen evaporated from the asphalt and we were back playing, the GTM-R and I. Now
we’re starting to test the car more, with confidence growing. We move past a Porsche GT3 RS
on the straight without much trouble. As the pace in this very short test built, my liking for the
car grew. In the slick conditions, she slipped just a bit at Turn 8, but was easily caught. Going
into Turn 11 (the slowest on the track) a bit hot once, she plowed just a tad as a breath of the
throttle got her to bite and go. Maybe this is not a high-tech package, but its fast and a blast to
drive. Again, turn-ins are just right, balance is excellent, and the power is more than adequate til
there’s more seat time in the car. The one serious concern as expressed to Richard is the brakes.
Carrying donor Corvette brakes with upgraded pads, I doubt whether this package is going to
take the car where it could otherwise go. The pedal was soft and I had to be pretty conservative
with this element of driving the car fast. On the other hand, HOD teaches “in slow, out fast” and
maybe that was working.
With only three real laps after getting to know the car, and slowing for the wet conditions, we got
her to a 2:02 lap time – I know, that’s not that quick for a car with these statistics – but it was just
three real laps in a borrowed car at a track day. I know this car goes WELL below the 2:00
minute mark. Richard and the team were immediately talking about more horsepower and other
upgrades, but my advice was to get a driver into the car for a focused test day, not a track day or
race weekend, upgrade at least the brake pads, and really push the package they have right now,
because it is VERY, VERY good. And I was devastated by the checkered flag. If I had not been
in charge of the event and feeling guilty for enjoying myself, I’d have loved to take her out
again, as I know we’d go well down on lap times. I enjoyed driving the GTM-R a LOT. In fact,
this is one of the most enjoyable cars I’ve driven on track. Having been “baptized,” I hope that
Richard’s team can start building more of these fun and hopefully very affordable cars.
Yes – I did this article backwards. I wrote about my experience and now here are some key facts
about the car. The GTM-R is a collaboration between Factory Five Racing,
http://www.factoryfive.com/table/ffrkits/GTM/GTMkit.html which builds the GTM kit for
$19,990 to the consumer, and the Prototype Development Group in Stockton, CA. Don’t be
mistaken, this is as grass roots as grass roots gets. Richard and his team have taken this project
on as a labor of love. The future of this car? Definitely focused on endurance racing with an
effort being prepared for this year’s 25 Hours of Thunderhill (they had a credible run last year
with some teething problems). The car is now approved for SCCA Super Production and NASA
Super-Touring 1 classes.
Here are some key specs on the car – keep in mind the most important thing here, BANG for the
BUCK! Many of the bits and pieces of this car came from Home Depot and other local hardware
stores.
Start with a Factory Five GTM supercar kit ($19,990) – mid-engine, rear-wheel drive
Engine: donor LS6 from a C5 Corvette
Front and rear suspension: Corvette donor
Transmission/transaxle: 993 Porsche
Brakes: Corvette donor with Tilton master cylinder
Go to www.prototypedevelopmentgroup.com for more information.